Went to look at a 2004, 90k mile 4.0 w/auto tranny today and there was a very pronounced clunk, especially from 1st to 2nd and 2nd 1st, coming form the rear.It will make this clunk .every upshift but is a softer clunk as it shifts up the up the gears. It seems to be more pronounced when driving under load.. any Ideas..

 

Go look at another truck.